code: def testScalarB(self):
      A = array([[1.0, 2.0]])
      b = 3.0
      x = lsmr(A, b)[0]
      assert norm(A.dot(x) - b) == pytest.approx(0)
  
imports: from numpy import array, arange, eye, zeros, ones, transpose, hstack
  from numpy.linalg import norm
  from numpy.testing import assert_allclose
  import pytest
  from scipy.sparse import coo_matrix
  from scipy.sparse.linalg._interface import aslinearoperator
  from scipy.sparse.linalg import lsmr
  from .test_lsqr import G, b
label_desc: Use image node_id 7 for calling the TestLSMR obj's underlying member method code with example usage: obj.testScalarB() without return types